The present invention generally relates to surgical procedures and, more particularly, to positioning and monitoring the position and configuration of surgical implements.
Endoscopes are well known in the field of medicine. Endoscopes with a soft insertion unit can be inserted into the lumen of a body cavity to diagnose problems located in a deep region in the body cavity without the necessity of incision and can also be used to guide treatment appliances to a desired location within the body cavity. In the past, medical practitioners have needed to use radio-opaque markers or contrast either in the patient or on the instruments (or both) in order to visualize instrument placement under fluoroscopy. In cases where x-ray exposure under fluoroscopy is contra-indicated or where the scheduling of procedures to occur in radiology is economically or logistically discouraging, alternative measures are needed that can substitute, for example, for injecting contrast into the gastrointestinal (GI) tract in order to “tattoo” a certain area which can be visualized on fluoroscopy; or for indicating the location of existing endoscopes or accessory devices—such as a stent deployment catheter, a Stretta radiofrequency catheter, or a dilator. One such accessory device is a clip that can be used, for example, to hold portions of tissue together. The clip can be inserted into the body cavity using a clip fixing device available, for example, from Olympus Corporation (Tokyo, Japan), Wilson-Cook Medical, Inc, (Winston-Salem, N.C., US), and Boston Scientific Corporation (Natick, Mass., US).
When inserting, for example, an endoscope, a guidewire, or clip fixing device, each of which includes a long flexible tube, it is possible for the tube to bend back on itself or form a loop or enter some other undesirable configuration. An endoscope, for example, typically has a steerable end that can be curved in different directions under the control of the operator and it is useful for the operator to know whether the configuration of the endoscope end is achieving a desired position and whether a position of a treatment appliance—such as a dilator, stent, or clip—relative to the position of the endoscope—for example, in some cases the appliance may be passed through the endoscope—is as desired. In the past fluoroscopy has been used to monitor the configuration of endoscopes. Recently, a colonoscope, which is a particular type of endoscope, known as ScopeGuide™ and marketed by Olympus Corporation, Tokyo, Japan, has electromagnetic coils which allow visualization of the colonoscope configuration on a monitor. A system for detecting the shape of an endoscope using source coils and sense coils via a detection system having a processor included in a control unit is disclosed in U.S. Patent Application Publication No. 20030055317, assigned to Olympus Optical Co., and incorporated by reference.
As can be seen, there is a need for positioning a variety of surgical instruments and monitoring the positions and configurations of those instruments while providing an alternative visualization to that offered by fluoroscopy.